I enabled it last night and just went and saw about 100 or 200 ads, almost all of which are relevant to my sites. That's great. However, when I visit my sites, I see all sorts of irrelevent ads that are not showing up in the Adsense review area.

I know I can block the URLs manually, but it would be great to actually know what ads other people are seeing besides me. I pretty much gave up on Adsense a few months ago because the ads went from being completely targeted to half of them being irrelevant (especially the sidebar skyscrapers - even after adding section targeting). But this new feature would be immensely helpful if it actually showed all the ads viewers see.

I use it, and it has sucked about 3 full working days just to block ads I don't want.

The interface is slow and clunky, although the functionality is very, very welcome.

I think they'd do better offering a sorted list of ad urls + content preview, a list say 100 long at a time, with simple checkboxes next to each, and an option to add domain or full url to blocked url list with 1 click.

Additionally, there seems to be no cross-referencing with your URL block list at all, so even if you block a whole domain, you end up wading through 20 or so of their ads, wasting more valuable time.

There is also no indication of where you are in the stream of previews, nor a way to jump ahead more than 12 or whatever your screen resolution allows.

I find the zoom-on-hover to be massively annoying, as it leads to plentiful accidental clicks which have to be reverted.

Using the marquee selection is pointless as the javascript is so very slow to respond.

I'm still not done blocking all ads I do not wish to see, and I have spent 3 working days on it, full time.

But they'll never do that, for the same reason they won't let publishers set a minimum bid for ad space - because then they're left with a bunch of cheap ad inventory that they can't place. And that would piss off the advertisers.